Since the time when land could first be owned and recorded, persons have sought ways to define and mark the metes and bounds of their property. Where natural barriers existed, such as streams, trees and mountains, markings were simplified. Where these barriers were absent, however, other methods were resorted to. Thus, stone stanchions, brick walls, barbed wire and wooden fencing have been used in one form or another.
In ancient times, property markings and related man-made walls or fencing were used for defensive purposes to protect against invasion by outsiders. Today, the typical use of fencing has a loftier purpose. In most cases, this "picket-fencing", as it has become known, is used to restrain and protect children and pets. In some instances, it is also used purely for decoration, such as around gardens, ponds, walkways, etc.
Picket fences have traditionally been made from wood. Although wood enables a relatively simple construction, it also has numerous disadvantages. Namely, it is subject to rot and thus requires regular maintenance in the form of painting, staining, post replacement, rebuilding, etc. The assembly of typical wooden fences is also time consuming and tedious. Usually, the individual pickets and horizontal rails have to be cut to length and assembled. Substantial care must also be taken when cutting the pickets and rails to ensure the desired appearance. The fence must then be assembled using nails or screws and, of course, cannot be readily disassembled and reassembled if it is desired to move the fence to an alternative location.
Against this background, various proposals have been made for forming picket fences and the like from materials other than wood. See, for example, U.S. Pat. Nos. 2,573,239 to Barrett, 2,685,432 to Murray, 2,766,967 to Roberts, 2,919,112 to Cofield, 3,212,754 to Revell, 3,411,752 to Bos, 4,625,948 to Lustvee, and 4,130,272 to Emmie. Each of these references discloses a relatively complex arrangement for manufacturing and installing a picket fence comprised of steel.
The Barrett U.S. Pat. No. 2,573,239 discloses a sheet metal picket fence arrangement. As shown, horizontal stringers and vertical pickets are fastened together by introducing projections on the stringers into openings in the pickets. The pickets have a complex cross-section necessary for such assembly. In addition, the stringers are fastened to the corner posts using bolts.
The Murray U.S. Pat. No. 2,685,432 discloses a metallic picket fence construction wherein certain pickets have bottom extensions for insertion into the ground. The pickets are fastened to the flexible rail strips by introducing projections on the pickets into openings on the rails strips. Mating rail strips are connected to each other through the use of fasteners.
The Roberts U.S. Pat. No. 2,766,967 discloses a knock-down fence construction and incorporates horizontal metal straps with tabs punched out from it. Also included are vertical slats with notches cut in the edges. As disclosed, the notches correspond to the punched tabs, and the slats are bowed, so as to enable them to engage the tabs. Although intended as a light-weight low fence for the edge of flower beds and similar applications, the horizontal rails slats do not provide a rigid construction. Moreover, the tab and notch arrangement prevents the slats to be aligned in anything but a right angle to the horizontal rails. Still further, after assembly, there is no means provided to permanently secure the slats in position. As a result, they can be accidentally or deliberately removed.
The Cofield U.S. Pat. No. 2,919,112 discloses a collapsible fence arrangement. As shown, horizontal stringers and vertical pickets are permanently rivetted together to enable relative rotation between them. As is readily seen, however, this arrangement does not permit easy disassembly.
The Revell U.S. Pat. No. 3,212,754 discloses an interlocking fence structure. A top rail specially formed with slots and tongues for engagement with vertical pickets. The pickets are similarly provided with a complex cross-section and projections for securing them in the top rail.
The Bos U.S. Pat. No. 3,411,752 discloses a guardrail construction, such as a balcony balustrade. Generally, I-section vertical members are provided which are accommodated in corresponding openings of top and bottom horizontal rails. As disclosed, pins secure the vertical members in the horizontal rails. A sheet form hand rail is further provided to cover the tops of the vertical members protruding through the top horizontal rail.
U.S. Pat. No. 4,625,948 to Lustvee discloses a picket fence construction having a transverse rail and a plurality of pickets adapted to be mounted in the rail. The pickets are hung by means of a tongue and engaging link arrangement. The rail includes a tongue for each picket, and each picket includes an engaging link. In the alternative, the tongue and links may be reversed.
U.S. Pat. No. 4,130,272 to Emmie discloses a picket fence having a plurality of parallel and laterally spaced metal pickets which are interconnected by a plurality of parallel pairs of stringers. The stringers are made from a metal material and have opposite ends shaped in a tubular configuration which are received in mating recesses on adjacent, parallel pickets such that the pickets are rotatable about the tubular configurations of the stringers. The pickets and their associated stringers are thus movable with respect to each other in such a manner that the pickets may be disposed along a curved path.
In an effort to overcome the difficulties of the aforementioned metallic fence constructions, efforts have also been directed to the design and manufacture of plastic resin structures. See, for example, U.S. Pat. No. 4,324,388 to Klaser, which discloses a fence structure wherein the components are fabricated from a plastic resin and where the corner, line or gate post present positive anchoring with ready installation. Although less complex than the above metallic designs, the all plastic resin approach of Klaser is far less secure and creates new difficulties in installation through the use of its component post anchors.
Consequently, a need has developed for an improved fence structure which may be easily installed and maintained and which provides a sturdy structure to serve both protective and ornamental purposes.